I'm pretty sure they used one of these. You can find them at Walmart in the haunted housewares department over by the bundles of sage and jugs of holy water. From what I hear, they work on all sorts of haints, apparitions, specters, vapors, as well as standard Casper-type ghosts. The only problem is that you have to take it to the place where they accept old oil, chemicals, and other toxic stuff for disposal. DO NOT empty it into your storm sewer! And whatever you do, do not cross the streams.
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